The present invention relates to a tinnitus rehabilitation device and method for providing relief and treatment to persons suffering from the disturbing effects of tinnitus and relates particularly, though not exclusively, to such a method and device that employs intermittent masking of the tinnitus.
Tinnitus is the perception of a sound in the absence of any corresponding external sound. It is most commonly perceived as a ringing, buzing, whirring type sound, but can also be perceived as a beating, or pounding sensation. Around one third of people who suffer from tinnitus can be quite highly disturbed by it. Continuous perception of tinnitus can lead to insomnia, an inability to relax, state and trait anxiety, depression, and even suicide in extreme cases. Often closely associated with tinnitus is the perception of hyperacusis, which is a great intolerance to external sounds, even the softer everyday sounds. This distressing condition can even occur as a precursor to tinnitus, and is thought to share the same underlying causes. Thus, every reference to tinnitus in this document should be construed as including the phenomena of hyperacusis or other types of loudness discomfort.
There are very few effective treatment options available for tinnitus sufferers, with the vast majority only being advised that xe2x80x9cyou""ll have to learn to live with itxe2x80x9d. Most patients find that they can far more readily ignore an external sound than their tinnitus. One palliative method has been to use hearing aid-style devices that produce a band of noise to totally mask the perception of the tinnitus. This gives a sense of relief and control over the tinnitus in around half of patients, but usually has no long-term effect. The prohibitive cost (around A$1500) and aesthetic considerations limits the proportion of sufferers for whom this is a viable measure. The presence of hearing loss for external sounds in the tinnitus region often means that the masking noise needs to be unpleasantly loud before the tinnitus can be masked, and the noise is often judged to be not much better than the tinnitus itself.
In the past four years, a new understanding of the neurophysiological processes underlying tinnitus has been published, emphasising the role of the neural pathways in the emergence of distressing tinnitus and the possibility of using this neural plasticity to retrain its perception. This has been dubbed xe2x80x9cTinnitus Retraining Therapyxe2x80x9d or TRT. In this technique, patients are given intensive counselling, and use noise generators at a volume that does not completely mask the tinnitus. Long term reductions in tinnitus disturbance have been achieved in some patients, but it is usual for this process to take at least 18 months of therapy before any substantial benefit occurs. TRT also offers very little immediate sense of relief from the tinnitus, and no relief from the associated sleep disturbance and inability to relax.
The closest known prior art to the invention is the xe2x80x9cSilentia Setxe2x80x9d developed by Starkey Corp., which is a pair of hearing aid devices which wirelessly receive signals from a stereo system via an induction loop under a pillow at bedtime. Recording of high frequency noise bands (xe2x80x9cwater soundsxe2x80x9d), babble noise, traffic sounds and music have been used to mask tinnitus using this system, however the high cost of the Silentia Set make it prohibitive for many sufferers.
Other prior art audiotherapeutic techniques using music are the Tomatis Method developed by Alfred A. Tomatis, and Auditory Integration Training. While neither method is designed for the treatment of tinnitus, the two techniques have some similarities in that they modify music for the treatment of auditory disorders. The Tomatis Method employs an xe2x80x9cElectronic Earxe2x80x9d developed by Alfred Tomatis, (U.S. Pat. No. 4,021,611). It has its origins from an extremely outdated model of how the auditory system works, and has been widely debunked by audiological organisations. Auditory Integration Training is based on the Tomatis Method, but presents the music at extremely loud levels, that may result in hearing damage, and importation of devices using this technique have been banned by the American Food and Drug Administration.
The present invention was developed with a view to providing a more effective rehabilitation technique and device for tinnitus sufferers that is consistent with contemporary understandings of the underlying pathology in the auditory system, of which tiruitus is a symptom.
Throughout this specification the term xe2x80x9ccomprisingxe2x80x9d is used inclusively, in the sense that there may be other features and/or steps included in the invention not expressly defined or comprehended in the features or steps subsequently defined or described. What such other features and/or steps may include will be apparent from the specification read as a whole.
According to one aspect of the present invention there is provided a tinnitus rehabilitation method for providing relief to a person suffering from the disturbing effects of tinnitus, the method comprising:
providing an audio signal spectrally modified in accordance with a predetermined masking algorithm designed to modify tie intensity of the audio signal at selected frequencies, and wherein said predetermined masking algorithm is specifically produced to account for the basic audiometric configuration of the person whereby, in use, when the spectrally modified audio signal is heard by the person it provides significant masking of the tinnitus.
Preferably the method further comprises the steps of:
transmitting, using a computer, data representing an audiogram of the person suffering from tinnitus;
processing said audiogram data at a remote location and producing required equalisation response data based on said audiogram data using said predetermined masking algorithm;
receiving, using a computer, said required equalisation response data; and,
combining said required equalisation response data with audio data representing said audio signal to produce said spectrally modified audio signal.
According to a second aspect of the invention there is provided a method of using a computer to provide access to a predetermined masking algorithm used in tinnitus rehabilitation, for providing relief to a person suffering from the disturbing effects of tinnitus, the method comprising:
receiving on-line, from a user, data representing an audiogram of the person suffering from tinnitus;
processing said audiogram data using said predetermined masking algorithm to produce required equalisation response data based on said audiogram data; and,
transmitting said required equalisation response data to the user.
According to a another aspect of the present invention there is provided a tinnitus rehabilitation sound recording for providing relief to a person suffering from the disturbing effects of tinnitus, the sound recording comprising:
an audio signal spectrally modified in accordance with a predetermined masking algorithm designed to modify the intensity of the audio signal at selected frequencies, and wherein said predetermined masking algorithm is specifically produced to account for the basic audiometric configuration of the person whereby, in use, when the sound recording is heard by the person it provides significant masking, of the tinnitus.
Preferably the predetermined masking algorithm provides intermittent masking of the tinnitus wherein, at a comfortable listening level, during peaks of the audio signal the tinnitus is substantially completely obscured, whereas during troughs the perception of the tinnitus occasionally emerges. In practice it has been found that such intermittent masking can provide all immediate sense of relief, control and relaxation for the person, whilst enabling sufficient perception of the tinnitus for habituation and long term treatment to occur.
Typically said predetermined masking algorithm is designed to modify the intensity of the audio signal across substantially the full spectral range of the audio signal. Preferably said audio signal is a highly dynamic signal in which the spectral content and intensity constantly varies over time. Most preferably the audio signal is a music signal. However other types of signals including speech or noise might also be employed.
Typically said predetermined masking algorithm is partly tailored to the hearing loss characteristic of the person. Preferably the spectral qualities of the audio signal are modified by the masking algorithm so as to provide a relatively equal sensation level across a major portion of the audio spectrum in both ears Typically said predetermined masking algorithm also incorporates a set of calibration figures such as for converting dB HL (Hearing Level) to dB SPL (Sound Pressure Level), or to correct for the presence of various coupling system types.
According to a still firer aspect of the present invention there is provided a tinnitus rehabilitation device for providing relief to a person suffering from the disturbing effects of tinnitus, the device comprising:
signal filtering means adapted to spectrally modify an audio signal in accordance with a predetermined masking algorithm designed to modify the intensity of the audio signal at selected frequencies, and wherein said predetermined masking algorithm is specifically produced to account for the basic audiometric configuration of the person whereby, in use, when the spectrally modified audio signal is heard by the person it provides significant masking of the tinnitus.
Preferably said signal filtering means is a programmable signal filtering means whereby, in use, the device can be programmed with a predetermined masking algorithm adapted to the particular needs of the individual suffering from tinnitus
In a preferred embodiment of the device the predetermined masking algorithm is of the form:
However, in an alternative software embodiment of the invention, the mathematical algorithm by which the individual prescription of the audio signal is calculated may differ from the above algorithm. Such other embodiments of the invention would be consistent with the essential clinical technique that is intended to provide a modification of the intensity of an audio signal to account for hearing levels specifically for the relief and/or treatment of tinnitus and hyperacusis.
Preferably the device is employed in conjunction with a personal music player (PMP) and has an input adapted to connect to the audio output headphone jack on the PMP. Preferably the device has a standard headphone jack to which a standard PMP headphone can be connected. Alternately, a transmitter may be used to transmit a signal to a wireless type of receiver that may be placed in the ear canal, concha area, behind the ear, or some other area relatively close to the ear.